Gentoo's Bugzilla –
Attachment 651158 Details for
Bug 734220app-emulation/fs-uae-3.1.62 fails to compile: blkdev.cpp:758:40: error: non-constant-expression cannot be narrowed from type 'int' to 'uae_u8' (aka 'unsigned char') in initializer list [-Wc++11-narrowing]